I do a buddy training session for two women (same age), and both women wear heart rate monitors during the session. Both clients have their age, height, weight, gender, and resting heart rate entered in to their HR monitors. At the end of a 30-minute session, Client “A” has burned 475 calories while Client “B” has burned only 320 calories. Client “B” is frustrated because she did the exact same work out as Client “A” and did not burn nearly as many calories. Based on the HR monitor readings, Client “A’s” max HR during the session was higher than Client “B’s.” Does this mean that Client “B” is more fit than Client “A” and that it is going to take more exertion for Client “B” to achieve the same calorie burn as Client “A?” Is Client “B” not working as hard as Client “A,” even though Client “B” feels like she worked as hard as she could during the workout? Could it be possible that both clients are equally fit and one just has a physically bigger heart than the other?
There are so many variables with this. It could be that that possibly Client A is fitter and has more efficient muscle tissue than client B, or their heart rate monitors are not calibrated to match each other, or, Client A has already done exercise prior to your workout and will then burn more calories than client B, or, Client A is working harder than client B
When you say Max Heart Rate, do you mean, Optimum?
My thoughts are mixed with this question.
I don’t like having my clients “compete” with one another, we all work out differently
Also, Heart Rate Monitors are only a part of the equation,. I would also go by waist/hip measurements, or skin fold measurements
I suggest having them switch heart rate monitors and see what happens.
as Susan says, there are many variables that serve as possible explanations.
One can be different body weights. By the calibration of caloric energy expenditure, a person with higher body weight will burn more calories if all else is equal.
Another: even though the ‘standard’ of heart rate training is 220 minus age and so on, the true maximum heart rate can vary quite a bit from person to person and can only be determined in a VO2 test. Heart rate monitors just operate with set formulas that cannot take that into account.
Another can be the manufacturer of the heart rate monitors.
I would leave that kind of competition alone and go by rating of perceived exertion which – by your description – appears to be very similar.
Hope this helps.
Hello Emily. “Nope” doesn’t mean that at all. Different people have different metabolic rates (including resting metabolic rates) so calorie burn is very ‘person specific.’ I like to use analogies, so I would analogize this to looking at heart rates as an example. Two people could run the same distance for example, and one of them might have a higher ‘exercise heart rate’ than the other. This does NOT automatically indicate that one was working harder than the other.
If you’re looking for comparisons, always compare the individual to themselves – in other words their calorie burn etc. with different exercise intensities compared to themselves at rest etc.
It is important to remember that the volume of oxygen consumed per minute is different for everybody.
Factors that influence V02 are, cardiac output, one’s level of conditioning, one’s body weight.
As fitness professionals we all know that at rest the average 70kg individual pumps 3.5ml/kg/min of oxygen. Every litre of oxygen consumes about 4-5 calories per minute. If one weighs more or less than those 70kg oxygen consumption or caloric expenditure is increase or decreased.
If the world were perfect and both clients A and B were of the same gender, same weight and equally conditioned the caloric expenditures would be the same.
Hope this helps.